<html>
<head>
<style type="text/css">
  table { width: 200px;             }
  td    { border: 1px solid black;  }
  td.a  { background: lightgreen;   }
  td.b  { background: orange;       }

  /* cellspacing=0 cellpadding=0 */
  table  { border-spacing: 0 }
  td, th { padding: 0 }
</style>
</head>
<body>
<table>
  <tr>
    <td class="a" width="100%">x</td>
    <td class="b">x</td>
  </tr>
  <tr>
    <td/><td/>
  </tr>
</table>
</body>
</html>
